{"id":"c44820de-8b11-5550-8c8a-b9c99272fdab","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-hf-larger-lvef-null","predicate":"does_not_improve_in_trial","statement":"Six months of thiamine did not improve LVEF, exercise capacity or quality of life in 69 ambulatory patients. Baseline-adjusted LVEF was higher with placebo (38%) than thiamine (35%), P=0.047.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"context_dependent","is_public":true,"mechanism_event_id":"e371ae6d-c82a-5001-b23d-a95aa440726a","mechanism_event_label":"The larger trial did not reproduce improved pumping; its adjusted LVEF comparison favored placebo.","subject":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"object":{"id":"9ea9182f-3a0a-51c6-94e7-36940d4017b3","slug":"left-ventricular-ejection-fraction","display_name":"Left ventricular ejection fraction","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"e371ae6d-c82a-5001-b23d-a95aa440726a","stable_key":"46d15d9e-d3b5-544d-ba01-b785aa3e4f42:b1-hf-larger-lvef-null-event","event_type":"observed_intervention","label":"The larger trial did not reproduce improved pumping; its adjusted LVEF comparison favored placebo.","description":"Six months of thiamine did not improve LVEF, exercise capacity or quality of life in 69 ambulatory patients. Baseline-adjusted LVEF was higher with placebo (38%) than thiamine (35%), P=0.047.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"d813f2a6-3ed1-54a7-84d2-d913bcda536f","slug":"exercise-capacity","display_name":"Exercise capacity","entity_type_key":"cellular_process"},"role":"parallel_endpoint","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"36b7c3eb-068b-500f-af1c-078829df1ecc","slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"9ea9182f-3a0a-51c6-94e7-36940d4017b3","slug":"left-ventricular-ejection-fraction","display_name":"Left ventricular ejection fraction","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""}]},"contexts":[{"dimension":"experimental_model","value_text":"Placebo-controlled multicenter trial.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"exposure","value_text":"200 mg oral thiamine mononitrate daily versus placebo for six months; trial exposure only.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"Dose, duration, participants and crossover versus parallel design differ from the earlier pilot; not a test of untreated beriberi or proof of universal cardiac harm.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Thiamine research collection; topical membership is not evidence of a direct dietary effect.","comparator":null,"unit":null,"notes":"","entity":{"slug":"thiamine","display_name":"Thiamine (vitamin B1)","entity_type_key":"small_molecule"}},{"dimension":"organism","value_text":"Homo sapiens","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"plain_language","value_text":"The larger trial did not reproduce improved pumping; its adjusted LVEF comparison favored placebo.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"primary_references","value_text":"[b1-keith2019] Thiamin supplementation does not improve left ventricular ejection fraction in ambulatory heart failure patients: a randomized controlled trial (2019). https://pubmed.ncbi.nlm.nih.gov/31504093/ DOI: 10.1093/ajcn/nqz192","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"tissue_or_cell_type","value_text":"Heart imaging and function","comparator":null,"unit":null,"notes":"","entity":null}],"evidence":[{"id":"e7b91b26-4229-50e5-90db-aebba831f17a","evidence_kind":"source_excerpt","locator":"Lines 1684-1694","start_line":1684,"end_line":1694,"excerpt":"### b1-hf-larger-lvef-null\nSix months of thiamine did not improve LVEF, exercise capacity or quality of life in 69 ambulatory patients. Baseline-adjusted LVEF was higher with placebo (38%) than thiamine (35%), P=0.047.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The larger trial did not reproduce improved pumping; its adjusted LVEF comparison favored placebo.\norganism: Homo sapiens\ntissue_or_cell_type: Heart imaging and function\nexperimental_model: Placebo-controlled multicenter trial.\nlimitations: Dose, duration, participants and crossover versus parallel design differ from the earlier pilot; not a test of untreated beriberi or proof of universal cardiac harm.\nexposure: 200 mg oral thiamine mononitrate daily versus placebo for six months; trial exposure only.\n[b1-keith2019] Thiamin supplementation does not improve left ventricular ejection fraction in ambulatory heart failure patients: a randomized controlled trial (2019). https://pubmed.ncbi.nlm.nih.gov/31504093/ DOI: 10.1093/ajcn/nqz192","model_system":"Placebo-controlled multicenter trial.","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. Study references: [b1-keith2019] Thiamin supplementation does not improve left ventricular ejection fraction in ambulatory heart failure patients: a randomized controlled trial (2019). https://pubmed.ncbi.nlm.nih.gov/31504093/ DOI: 10.1093/ajcn/nqz192","relationship":"supports","weight":1.0,"link_notes":"","source":{"id":"158d2c03-ac8c-589f-8270-c468165ae346","stable_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","title":"Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17)","document_type":"imported_text","citation_label":"AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text.","file_path":"","sha256":"f376512fb3310141315548015b387833e3af45146e73fb73cd02cee20e4ddb9c","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","review_status":"unverified_draft","notes":""}}],"relations":[],"conflicts":[{"id":"7e15b9aa-0cd7-5c5a-bb0e-e17095c2c454","title":"Does thiamine supplementation improve LVEF in chronic heart failure?","kind":"contradiction","status":"open","why":"The small crossover pilot reported an LVEF benefit; the larger six-month ambulatory trial found no improvement. These are differing trial outcomes, not a correction to a drafting error.","resolution":"Unresolved across trial settings. Compare baseline thiamine status, diuretic exposure, heart-failure severity, dose/form, duration, statistical uncertainty and crossover versus parallel design. The studies do not establish which modifier accounts for the differing results, and neither justifies treating all heart failure as thiamine deficiency.","created_at":"2026-09-17 10:00:09","record_type":"conflict","display_label":"Recorded conflict","record_url":"/conflicts/7e15b9aa-0cd7-5c5a-bb0e-e17095c2c454","sides":[{"conflict_id":"7e15b9aa-0cd7-5c5a-bb0e-e17095c2c454","ordinal":0,"label":"Positive nine-patient crossover pilot","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","start_line":1672,"end_line":1682,"quote":"### b1-hf-pilot-lvef-positive\nThe nine-patient crossover trial reported an absolute LVEF treatment effect of 3.9 percentage points after 28 days.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: A very small heart-failure trial reported improved pumping fraction.\norganism: Homo sapiens\ntissue_or_cell_type: Heart imaging\nexperimental_model: Nine diuretic-treated patients; randomized crossover.\nlimitations: Small pilot with short periods; not proof that all heart failure is B1 deficiency.\nexposure: 300 mg/day thiamine versus placebo for 28 days, six-week washout then crossover; trial exposure only.\n[b1-schoenenberger2012] Thiamine supplementation in symptomatic chronic heart failure: a randomized, double-blind, placebo-controlled, cross-over pilot study (2012). https://pubmed.ncbi.nlm.nih.gov/22057652/ DOI: 10.1007/s00392-011-0376-2","source_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","source_title":"Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17)","claim_ids":["7816db70-793b-5187-ad8c-503795fb8183"]},{"conflict_id":"7e15b9aa-0cd7-5c5a-bb0e-e17095c2c454","ordinal":1,"label":"Larger six-month trial without improvement","revision_id":"53bc5eda-dec8-58cc-a56f-a9eb4ab036ef","start_line":1684,"end_line":1694,"quote":"### b1-hf-larger-lvef-null\nSix months of thiamine did not improve LVEF, exercise capacity or quality of life in 69 ambulatory patients. Baseline-adjusted LVEF was higher with placebo (38%) than thiamine (35%), P=0.047.\nCondition category: normal\nnutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect.\nplain_language: The larger trial did not reproduce improved pumping; its adjusted LVEF comparison favored placebo.\norganism: Homo sapiens\ntissue_or_cell_type: Heart imaging and function\nexperimental_model: Placebo-controlled multicenter trial.\nlimitations: Dose, duration, participants and crossover versus parallel design differ from the earlier pilot; not a test of untreated beriberi or proof of universal cardiac harm.\nexposure: 200 mg oral thiamine mononitrate daily versus placebo for six months; trial exposure only.\n[b1-keith2019] Thiamin supplementation does not improve left ventricular ejection fraction in ambulatory heart failure patients: a randomized controlled trial (2019). https://pubmed.ncbi.nlm.nih.gov/31504093/ DOI: 10.1093/ajcn/nqz192","source_key":"import-46d15d9e-d3b5-544d-ba01-b785aa3e4f42","source_title":"Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17)","claim_ids":["c44820de-8b11-5550-8c8a-b9c99272fdab"]}]}],"corrections":[],"research":null}